-LRB- CNN -RRB- -- An American man has been detained in North Korea , two State Department officials told CNN .

Diplomatic sources speaking on condition of not being identified said the man is a Korean-American businessman . One of the sources said the businessman had a visa to enter North Korea .

The State Department is working with the Swedish Embassy in the North Korean capital , Pyongyang , the officials said . The United States is urging North Korean authorities , through the Swedes , to release the man on humanitarian grounds .

Sweden represents America 's interests in North Korea because the United States and North Korea do not have diplomatic relations .

The Swedes have been granted consular access to the man and have visited him , the officials said . The Swedes are asking for regular visits , the officials said .

A Swedish official in Stockholm confirmed to CNN that the embassy in Pyongyang is working on the case .

The sources declined to provide additional information because of privacy concerns .

North Korea has detained several Americans in recent years , increasing tension levels in what is already a rocky relationship between Pyongyang and Washington .

In 2010 , former President Jimmy Carter helped secure the release of Aijalon Mahli Gomes , a U.S. citizen who had been fined roughly $ 600,000 and sentenced to eight years of hard labor for crossing over the Chinese border into North Korea .

Gomes , who attempted to commit suicide while in North Korean custody , was believed to be a Christian activist .

Two American journalists -- Laura Ling and Euna Lee , who had entered North Korea in March 2009 and were arrested and sentenced to 12 years hard labor -- were released in August 2009 after an intervention by former U.S. President Bill Clinton .

Tensions between North Korea and the West have spiked in recent years due in part to concerns over Pyongyang 's nuclear development program . The United States and South Korea held joint military drills in February , despite North Korea 's warning to the South not to carry out the drills , calling them a provocation and threatening to engulf Seoul in a `` sea of flames . ''

South Korea accuses the North of torpedoing and sinking one of its warships in March 2010 , killing 46 sailors , and last November , North Korea shelled Yeonpyeong Island , killing two South Korean marines and two civilians .

CNN 's Paula Hancocks contributed to this report

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NEW : Sources say the detainee is a Korean-American businessman

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The State Department is working on the case with the Swedish Embassy in Pyongyang

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North Korea has detained several Americans in recent years